Grappler systems for the picking up and transferring of loads are disclosed, for example, in Lanigan et al. U.S. Pat. Nos. 4,546,891; 4,667,834; 4,715,762; and 5,415,517, among others.
These devices are particularly adapted to pick up and move containers such as large metal shipping or load containers and even truck trailers (which are included in the term "containers"). Also, the devices of the previous patents include grapplers which are capable of gripping and lifting more than one container in a stack, to transfer several containers at once.
By this invention, systems for lifting and transferring load containers are improved, in that they can vary the dimensions of the distribution of the lifting latches carried by the system, so that containers of differing sizes may be lifted and moved. Also, a system is provided for facilitating alignment of the lifting latches with apertures on the load containers, so that the load containers may be reliably, easily, and safely gripped for lifting without the need for close-up visual adjustment. Rather, the operator in the cab of the system can quickly and effectively make such latching contact with various sizes of containers.
Also, the system of this invention may be folded up for travel into a relatively compact unit, permitting easier shipping and the like.